杏吧原创

ELVIS is still alive, say a pair of respected cosmologists. Not only that but
Marilyn Monroe came up with the theory of relativity, the dinosaurs survived and
went on to invent the automobile and Al Gore, not George Bush, is the US
President. 鈥淚n fact, as long as a history is consistent with the laws of
physics, it will not only happen but happen an infinite number of times,鈥� says
Alexander Vilenkin of Tufts University in Medford, Massachusetts.

It seems far-fetched but Vilenkin and Jaume Garriga of the Independent
University of Barcelona say it鈥檚 just a logical consequence of
鈥渋nflation鈥濃�攖he most widely accepted model of the Universe鈥檚 birth.
Inflation says the early Universe expanded extremely rapidly. This expansion was
so fast, the researchers believe, that distant regions of the Universe have been
entirely isolated from each other ever since, because light hasn鈥檛 had time to
travel between them.

Because of the inherent randomness involved in the formation of stars and
galaxies, each of these 鈥淥-regions鈥� should develop differently鈥攁nd have a
different history. Because inflation also predicts that the Universe is
infinite, this means there are an infinite number of O-regions too. But Vilenkin
and Garriga wondered if the number of possible histories is also infinite.

They reasoned that you cannot examine a particular O-region in infinitely
fine detail. There is a quantum 鈥渂lurriness鈥� to space that makes it impossible
to tell apart histories that are very similar to each other. 鈥淲e calculate that
there cannot be more than 10 to the power of 10¹⁵⁰ distinct histories,鈥� says
Vilenkin. 鈥淚t鈥檚 a fantastically huge number but it isn鈥檛 infinite.鈥�

So, if there are an infinite number of O-regions but a finite number of
histories, every possible version of history will occur, and it will occur an
infinite number of times. 鈥淣ot only is Elvis still alive but an infinite number
of Elvises are still alive,鈥� says Vilenkin.

Vilenkin admits that this might cause people to take a fatalist view of
existence. Although there may be O-regions where tax does not exist, there may
be others where Hitler won the Second World War or the Cuban missile crisis led
to global annihilation. 鈥淚 find the idea that all bad things happen very
depressing I admit,鈥� says Vilenkin.

Alan Guth of the Massachusetts Institute of Technology, the 鈥渇ather鈥� of
inflation, doesn鈥檛 offer any get-out. 鈥淚 don鈥檛 see any weaknesses or flaws in
the work,鈥� he says. So if inflation is correct鈥攁nd several experiments
recently gave it strong support
(New 杏吧原创, 5 May, p 6)
鈥攖he worst may
already have happened somewhere out there. And, as light continues to travel
further and further, O-regions will continue to grow and increasingly to
overlap.